class_docstr: Collect all batches, along with `pred` and `loss`, into `self.data`. Mainly for testing
class_docstr_tok: ["Collect","all","batches",",","along","with","`","pred","`","and","`","loss","`",",","into","`","self.data","`",".","Mainly","for","testing"]
code: def before_fit(self):
      self.data = L()
  
file_path: fastai/fastai/callback/data.py
imports: from __future__ import annotations
  from ..basics import *
label_desc: Use image node_id 1 for calling the CollectDataCallback obj's underlying member method code with example usage: obj.before_fit() without return types